A 35mm camera, based on the Canonet G-III QL17 rangefinder, simulated in Python.
The purpose of this project is to explore and understand the logic in the mechanisms of a camera by using object-oriented programming to represent real-world objects. It's also a way to appreciate the intricate mechanical logic embodied in a device like a camera.
It aims towards completeness in its modelling of the real world. For example, if you open the back of the camera in daylight with a partially exposed film, it will ruin the film.
See the c is for Camera documentation.
Clone the repository:
git clone https://github.com/evildmp/C-is-for-Camera.gitor:
git clone git@github.com:evildmp/C-is-for-Camera.gitIn the C-is-for-Camera directory, start a Python 3 shell.
>>> from camera import Camera
>>> c = Camera()See the camera's state:
>>> c.state()
================== Camera state =================
------------------ Controls ---------------------
Film speed: 100 ISO
Selected speed: 1/125
------------------ indicators -------------------
Light meter reading ƒ/16
Frame counter: 0
------------------ Mechanical -------------------
Back closed: True
Lens cap on: False
Film advance mechanism: False
Shutter cocked: False
Shutter timer: 1/128 seconds
Iris aperture: ƒ/16
Camera exposure settings: Shutter priority EV
------------------ Metering ---------------------
Metered light: 4096 cd/m^2
Exposure target: 15.0 EV
Mode: Shutter priority
Battery: 1.44 V
Film speed: 100 ISO
------------------ Film -------------------------
Speed: 100 ISO
Rewound into cartridge: False
Exposed frames: 0 (of 24)
Ruined: False
------------------ Environment ------------------
Scene luminosity: 4096 cd/m^2Advance the film:
>>> c.film_advance_lever.wind()
On frame 0 (of 24)
Advancing film
On frame 1 (of 24)
Cocking shutter
Applying aperture value ƒ/1.7 to iris
CockedRelease the shutter:
>>> c.shutter_button.press()
Light meter reading: ƒ1/16
Applying aperture value ƒ/16 to iris
Shutter opening for 1/128 seconds
Shutter closes
Shutter uncockedIt's not possible to advance the mechanism twice without releasing the shutter:
>>> c.film_advance_lever.wind()
On frame 1 (of 24)
Advancing film
On frame 2 (of 24)
Cocking shutter
Applying aperture value ƒ/1.7 to iris
Cocked
>>> c.film_advance_lever.wind()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/Users/daniele/Repositories/camera/camera.py", line 163, in wind
self.camera.film_advance_mechanism.advance()
File "/Users/daniele/Repositories/camera/camera.py", line 178, in advance
raise self.AlreadyAdvanced
camera.AlreadyAdvancedIf you open the back in daylight it ruins the film:
>>> c.back.open()
Opening back
Resetting frame counter to 0
'Film is ruined'Close the back and rewind the film:
>>> c.back.close()
Closing back
>>> c.film_rewind_mechanism.rewind()
Rewinding film